• Asian Pacific Journal of Cancer Prevention
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• v.15 no.9
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• pp.3927-3932
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• 2014

Background: Epidermal growth factor receptor (EGFR) mutations and echinoderm microtubule associated protein like 4-anaplastic lymphoma kinase (EML4-ALK) define specific molecular subsets of lung adenocarcinomas with distinct clinical features. Our purpose was to analyze clinical features and prognostic value of EGFR gene mutations and the EML4-ALK fusion gene in lung adenocarcinoma. Patients and Methods: EGFR gene mutations and the EML4-ALK fusion gene were detected in 92 lung adenocarcinoma patients in China. Tumor marker levels before first treatment were measured by electrochemiluminescence immunoassay. Results: EGFR mutations were found in 40.2% (37/92) of lung adenocarcinoma patients, being identified at high frequencies in never-smokers (48.3% vs. 26.5% in smokers; P=0.040) and in patients with abnormal serum carcinoembryonic antigen (CEA) levels before the initial treatment (58.3% vs. 28.6%, P=0.004). Multivariate analysis revealed that a higher serum CEA level before the initial treatment was independently associated with EGFR gene mutations (95%CI: 1.476~11.343, P=0.007). We also identified 8 patients who harbored the EML4-ALK fusion gene (8.7%, 8/92). In concordance with previous reports, younger age was a clinical feature for these (P=0.008). Seven of the positive cases were never smokers, and no coexistence with EGFR mutation was discovered. In addition, the frequency of the EML4-ALK fusion gene among patients with a serum CEA concentration below 5ng/ml seemed to be higher than patients with a concentration over 5ng/ml (P=0.021). No significant difference was observed for time to progression and overall survival between EML4-ALK-positive group and EML4-ALK-negative group or between patients with and without an EGFR mutation. Conclusions: The serum CEA level before the initial treatment may be helpful in screening population for EGFR mutations or EML4-ALK fusion gene presence in lung adenocarcinoma patients.

• Animal cells and systems
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• v.7 no.3
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• pp.255-259
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• 2003

Mutations in the factor Ⅴ gene are major risk markers for venous thrombosis. Several factors for blood coagulation have been related with cardiovascular disease. Ⅰ investigated genotype distribution for three mutations (G1691 A, A2379G and G2391 A) of the factor Ⅴ gene in the Korean population. Genotype frequencies were examined by polymerase chain reaction in 135 patients with coronary artery disease (CAD) and 116 healthy subjects. For the G1691A mutation (factor Ⅴ

• Journal of Microbiology and Biotechnology
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• v.18 no.9
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• pp.1584-1589
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• 2008

Although resistance of Helicobacter pylori to clarithromycin is a major cause of failure of eradication therapies, little information is available regarding gene mutations of clarithromycin-resistant primary and secondary H. pylori isolates in Korea. In the present study, we examined gene mutations of H. pylori 238 rRNA responsible for resistance to clarithromycin. DNA sequences of the 238 rRNA gene in 21 primary clarithromycin-resistant and 64 secondary clarithromycin-resistant strains were determined by PCR amplification and nucleotide sequence analyses. Two mutations of the 238 rRNA gene, A2143G and T2182C, were observed in primary clarithromycin-resistant isolates. In secondary isolates, dual mutation of A2143G+T2182C was frequently observed. In addition, A2143G+T2182C+ T2190C, A2143G+T2182C+C2195T, and A2143G+T2182C+A2223G were observed in secondary isolates. Furthermore, macrolide binding was tested on purified ribosomes isolated from T2182C or A2143C mutant strains with $[^{14}C]$erythromycin. Erythromycin binding increased in a dose-dependent manner for the susceptible strain but not for the mutant strains. These results indicate that secondary isolates show a greater variety of 238 rRNA gene mutation types than primary isolates, and triple mutations of secondary isolates are associated with A2143G+T2182C in H. pylori isolated from Korean patients.

• Biomedical Science Letters
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• v.10 no.4
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• pp.507-514
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• 2004

The Pseudomonas aeruginosa isolated from the clinical specimens has a mutation on the QRDR (quinolone resistance determining region). There were obvious mutations in both gyrA and parC gene which are major targets of quinolone. Simultaneous mutations were found two sites or more on these genes in all of ten strains. GyrB or parE gene had only silent mutation without converted amino acids. We confirmed that P. aeruginosa from clinical specimens exhibited decreased sensitivity to fluroquiolone due to changed Thr-83→lle and Asp-87→Asn types on gyrA and altered Ser-87→Leu type on parC. This is the first finding that a new Met-93→Thr type on parC as well as mutations on gyrB or parE genes differed from existing patterns. This study showed more mutations of gyrA rather than parC, suggesting that change of Type Ⅳ topoisomerase is more serious than that of type Ⅱ (DNA gyrase).

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.8
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• pp.4509-4513
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• 2013

Chronic hepatitis B virus (HBV) infection has long been the most common cause of hepatocellular carcinoma (HCC). However, some aspects of the pathogenesis of HBV infection and genesis of hepatitis B virus (HBV)-related hepatocellular carcinoma (HCC) are still inconclusive. An increasing number of published studies indicate that hepatitis B virus mutations are associated with risk of HCC. These variations include, in particular, mutations in ORF S,C,X gene regions. This mini-review summarizes results of clinical studies and molecular mechanisms on the possible relations of HBV mutations with the development of hepatocellular carcinoma.

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.12
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• pp.4915-4920
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• 2015

Background: : Familial adenomatous polyposis (FAP) is an autosomal dominant inherited disease mainly caused by mutations of the adenomatous polyposis coli (APC) gene with almost complete penetrance. These colorectal polyps are precancerous lesions that will inevitable develop into colorectal cancer at the median age of 40-year old if total proctocolectomy is not performed. So identification of APC germline mutations has great implications for genetic counseling and management of FAP patients. In this study, we screened APC germline mutations in Chinese FAP patients, in order to find novel mutations and the APC gene germline mutation characteristics of Chinese FAP patients. Materials and Methods: The FAP patients were diagnosed by clinical manifestations, family histories, endoscope and biopsy. Then patients peripheral blood samples were collected, afterwards, genomic DNA was extracted. The mutation analysis of the APC gene was conducted by direct polymerase chain reaction (PCR) sequencing for micromutations and multiplex ligation-dependent probe amplification (MLPA) for large duplications and/or deletions. Results: We found 6 micromutations out of 14 FAP pedigrees, while there were no large duplications and/or deletions found. These germline mutations are c.5432C>T(p. Ser1811Leu), two c.3926_3930delAAAAG (p.Glu1309AspfsX4), c.3921_3924delAAAA (p.Ile1307MetfsX13), c3184_3187delCAAA(p.Gln1061AspfsX59) and c4127_4126delAT (p.Tyr1376LysfsX9), respectively, and all deletion mutations resulted in a premature stop codon. At the same time, we found c.3921_3924delAAAA and two c.3926_3930delAAAAG are located in AAAAG short tandem repeats, c3184_3187delCAAA is located in the CAAA interrupted direct repeats, and c4127_4128 del AT is located in the 5'-CCTGAACA-3', 3'-ACAAGTCC-5 palindromes (inverted repeats) of the APC gene. Furthermore, deletion mutations are mostly located at condon 1309. Conclusions: Though there were no novel mutations found as the pathogenic gene of FAP in this study, we found nucleotide sequence containing short tandem repeats and palindromes (inverted repeats), especially the 5 bp base deletion at codon 1309, are mutations in high incidence area in APC gene,.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.6
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• pp.3705-3709
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• 2013

Background: To investigate epidermal growth factor receptor (EGFR) gene mutations in patients with non-small cell lung cancer (NSCLC) and to analyze any relationship with clinicopathological features and prognosis. Materials and Methods: EGFR gene exons 18-21 in 48 specimens of paraffin-embedded tumor tissue from NSCLC patients were amplified by PCR, followed by direct sequencing and analysis of links to clinicopathological features and prognosis. Results: EGFR mutations were detected in 18 of 48 (42.6%) patients with NSCLC. There were 9 cases of mutations in exon 20, 7 in exon 19 and 2 in exon 21. Mutations were more frequently observed in women (5/7 pts, 71.4%) than in men (13/41 pts, 31.7%) (p=0.086) and in non-smokers (5/5 pts, 100%) than smokers (13/43 pts, 30.2%). There was negative correlation of EGFR mutations with smoking status (p=0.005). EGFR mutations were more frequently observed with adenocarcinoma histology (13/32 pts, 40.6%) than in other types (5/16 pts, 31.3%) (p=0.527). The patients with EGFR mutations had better survival than those with wild-type EGFR (p=0.08). There was no association of EGFR mutations with metastatic spread. Conclusions: EGFR mutations in NSCLC were here demonstrated more frequently in females, non-smokers and adenocarcinoma histology in the western region of Turkey. Patients with EGFR mutations have a better prognosis.

• BMB Reports
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• v.29 no.5
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• pp.442-447
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• 1996

Mutations in codon 12, 13 and 61 of one of the three ras genes, H-ras, K-ras and N-ras, convert these genes into active oncogenes. The presence of H-ras gene mutations have important prognostic implications in various cancers. In this study, the H-ras gene mutations were investigated by two-step PCRRFLP in patients with bladder and stomach cancer. For the control experiments, T24 and SK2 cell lines were used. In a total of 36 bladder cancer patient cases, five (13.9%) mutations were found by this method. Of these, point 12 mutations were two (5.6%) cases and point 61 mutations were three (8.3%) cases. On the other hand, H-ras mutation was not found in 29 cases of stomach cancer. The results of the mutated H-ras gene confirmed by direct sequencing analysis were correlated well with PCR analysis. From the sensitivity test, the H-ras mutation was found to have about 0.2% of mutated DNA mingled in normal DNA. In conclusion, the H-ras mutation has a higher clinical Significance in bladder cancer than stomach cancer. Moreover the two-step PCR-RFLP method is sensitive, rapid and relatively simple for clinical work in detecting H-ras point mutations.

• Asian Pacific Journal of Cancer Prevention
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• v.17 no.4
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• pp.1725-1727
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• 2016

Breast cancer contributes to approximately 23% of the cancer cases identified and 14% of cancer related deaths worldwide. Including a strong association between genetic and environmental factors, breast cancer is a complex and multi factorial disorder. Two high penetration breast cancer susceptibility genes (BRCA1 and BRCA2) have been identified, and germ line mutations in these are thought to account for between 5% and 10% of all breast cancer cases. The human BRCA1 gene, located on 17q, is involved in the regulation of cell proliferation by aiding in DNA repair, transcriptional responses to DNA damage and cell cycle check points. Mutations in this gene enhance cell proliferation and facilitate formation of tumors. Two mutations, the 185 deletion of AG and the 4627 substitution from C to A, are founder mutations in the BRCA1 gene for breast cancer in Asian populations. Allele specific PCR was performed to detect these selected mutations in 120 samples. No mutation of 4627 C to A was detected in the samples and only one of the patients had the 185 del AG mutation in the heterozygous condition. Our collected samples had lower consanguinity and family history indicating the greater involvement of environmental as compared to genetic factors.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.2
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• pp.1073-1075
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• 2013

Background: In normal cells, activated epidermal growth factor receptor (EGFR) molecules are subjected to ubiquitination-mediated proteasome degradation pathway by c-Cbl, an ubiquitin ligase that checks uncontrolled proliferation. Hence expression of wild type c-Cbl molecule is essential to keep this degradation machinery in a functional state. Loss of expression or function of c-Cbl may consequently lead to sustained activation of EGFR and promote carcinogenesis, loss of function mutations in the c-Cbl gene already being reported in lung and hematopoietic cancers. However, the genetic status of c-Cbl in oral squamous cell carcinoma (OSCC) is not known. Hence in the present study we investigated the genomic DNA isolated from OSCC tissue biopsy samples for mutations in the RING finger domain coding region of c-Cbl gene, which has also been reported to be most frequently mutated in other cancers. Materials and Methods: Total genomic DNA isolated from thirty two post surgical OSCC tissue samples were amplified using primers flanking the exon 8 of c-Cbl gene that codes for the RING finger domain. The PCR amplicons were then resolved in a 1.2% agarose gel, purified and subjected to direct sequencing to screen for mutations. Results: The sequencing data of the thirty two OSCC samples did not identify mutations in the RING finger domain coding region of c-Cbl gene. Conclusions: To the best of our knowledge, this is the first time that the genetic status of c-Cbl gene in OSCC samples has been investigated. The present data indicates that genetic alteration of RING finger domain coding region of c-Cbl gene is relatively infrequent in OSCC samples.